Sitz bath basin



FIG. 1 is a perspective view of a sitz bath basin, showing my new design;

FIG. 2 is a top view thereof;

FIG. 3 is a side view showing one side thereof, the other side being a mirror image of the side shown;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a bottom view thereof. 

The ornamental design for a sitz bath basin, as shown and described. 